Apparatus for winding thin film into a roll at high speed



R. W. YOUNG June 11, 1968 APPARATUS FOR WINDING THIN FILM INTO A ROLL ATHIGH SPEED 25 Sheets-Sheet 1 Filed Jan. 19, 1966 ROGER W. YOU/V6 INVENTOR.

R. W. YOUNG June 11, 1968 APPARATUS FOR WINDING THIN FILM INTO A ROLL ATHIGH SPEED 5 Sheets-Sheet Filed Jan. 19, 1966 R0 GER W. YOUNG INVENTOR.

DRIVE Y June 11, 1968 R. w. YOUNG 3,337,798

APPARATUS FOR WINDING THIN FILM INTO A ROLL AT HIGH SPEED Filed Jan. 19,1966 5 Sheets$heet 5 ROGER W. YOU/V6 INVENTOR 3,337,798 APPARATU5 FORWINDING THIN FILM INTU A R'OLL AT HIGH SPEED Roger W. Young, UpperMontclair, N1, assignor to John Dusenhery Company, Inc., Clifton, N..I.,a corporation of New Liersey Filed Jan. 19, 1966, Ser. No. 521,663 11Claims. (Cl. 242-67.1)

ABSTRACT 6F TEE DISCLOSURE A pivotally-mounted arm carries a contactroller which engages a strip of film as the film is wound onto arotating core. The arm also carries a hollow, tubular, airpermeablemember connected to a source of air under pressure, the strip of filmpassing over the tubular member as it moves to the core.

This invention relates to a machine for winding a plurality of narrowstrips of thin film onto individual cores carried by a mandrel and moreparticularly to novel apparatus for winding the strips into smooth rollsat a high speed.

In machines of the class to which this invention is directed, arelatively wide web of thin material is slit into a plurality of narrowstrips and wound into rolls on individual cores. A variable factor whicheffects the winding of the rolls is the normal variation in thethickness or gauge of the particular material. Accordingly, it is thepractice to mount the cores on a common mandrel in such manner that eachcore can slip on the mandrel independently of the other cores to anextent corresponding to the tension of the strip of material being woundthereon. Generally, this is accomplished by inserting spacer rings ontothe mandrel between each core. Such spacer rings are individually keyedto the mandrel and the assembly of cores and spacer rings is clamped,axially, by suitable loading means carried at each end of the mandrel.Thus, the spacer rings are positively driven by the mandrel while eachcore is free to slip, relative to the mandrel, as the tension of theassociate strip exceeds the frictional force exerted against the coreends by the adjacent spacer rings. This arrangement is commonly referredto as differential wind- Another problem, particularly associated withthe winding of relatively narrow strips of thin film at high speeds, isthe entrapment of air between the convolutions of the strip as it iswound. This results in the uneven winding of g the rolls, that is, theconvolutions of the roll do not have an even tension and the side edgesthereof do not lie in a smooth plane. Various winding arrangements havebeen proposed to overcome this problem, but these are not entirelysatisfactory as they are not adapted for high speed operation and/or areso constructed that the film may be damaged during the windingoperation.

Winding apparatus made in accordance with this invention producessmoothly wound rolls of relatively narrow strips of thin film at a speedof 1,000 feet per minute. Although the apparatus has general utility inthis field, it is particularly adapted for winding film having athickness of the order of 0.25 mil and which has been slit into narrowribbons having a width of A2 to 1.0 inch.

An object of this invention is the provision of improved apparatus forwinding a strip of thin material into a roll at high speed.

An object of this invention is the provision of apparatus for winding arelatively narrow strip of thin film on a core, which apparatus includesmeans for minimizing the entrapment of air between the layers of thefilm as it is being wound and means for maintaining an edge of the filmin a precise path of travel as it passes onto the core.

States Patent lCC An object of this invention is the provision ofapparatus for winding narrow strips of thin film into rolls onindividual cores, which apparatus includes novel guide means associatedwith each core and effective to guide the strip as it is being woundthereon, thereby to produce Wound rolls wherein the edges of theconvolutions are aligned within a close tolerance.

An object of this invention is the provision of apparatus for winding anarrow strip of thin film into a roll on a core at a high speed, whichapparatus comprises a pivotally-mounted arm, a contact roller pivotallycarried by the arm and engaging the film as it is being wound on thecore, an air-permeable tubular member carried by said arm, and means formaintaining air under pressure in the tubular member, the strip of filmpassing over the tubular member as it passes onto the core.

These and other objects and advantages of the invention will becomeapparent from the following description when taken with the accompanyingdrawings. It will be understood, however, that the drawings are forpurposes of illustration and are not to be construed as defining thescope or limits of the invention, reference being had for the latterpurpose to the claims appended hereto.

In the drawings wherein like reference characters denote like parts inthe several views:

FIGURE 1 is a diagrammatic representation, in side elevation, showingwinding apparatus made in accordance with this invention;

FIGURE 2 is a side elevational view of the pivotallymounted guide armand associated components;

FIGURE 3 is a cross-sectional view taken along the line IIIIII of FIGURE2;

FIGURE 4 is an elevational view showing the free end of the guide arm;

FIGURE 5 is a cross-sectional view taken along the line V-V of FIGURE 2,and drawn to an enlarged scale;

FIGURE 6 is a central, cross-sectional view showing a modifiedconstruction of the air bearing;

FIGURE 7 is a side elevational View showing a modification of thecontact roller; and

FIGURE 8 is a fragmentary view, similar to FIGURE 2, but showing two airbearings carried by the guide arms.

Reference now is made to FIGURE 1 wherein the numeral 10 identifiesrelatively narrow strips of thin material such as, for example, tape foruse in recording-reproducing apparatus. These strips have been formedfrom a wide web of the material by a conventional continuous slittingoperation and pass over an idler roll 11 and a pull roll 12 driven at aconstant speed. Adjacently disposed strips are directed to spacedwinding stations of the machine and wound into individual rolls.Specifically, the odd-numbered strips, identified by the numeral 13,pass over the idler rolls 14 and 15 to a first winding station, Whereasthe even-numbered strips, identified by the numeral 16, pass over theidler rolls 17 and 18 to a second winding station. Poistioned in thefirst winding station is a mandrel 20 carrying a plurality of cores, theend core 21 being visible in this particular view. The cores are spacedapart a distance corresponding to the width of the cut strips by meansof individual spacer rings individually keyed to the mandrel. Suchassembly of cores and spacer rings is clamped, axially, by suitablemeans carried at each end of the mandrel, whereby the ends of the coresare pressed into frictional contact with the ends of the spacer rings,as is conventional in this art.

Before the start of the winding operation, the ends of the cut strips ofmaterial are afiixed to the associated cores, as by adhesive tape. Themandrel 20, driven by a separate motor, is then rotated at a speed tomaintain a predetermined tension on the strips as they are being woundon the associated cores. This results in a slippage of the cores,relative to the mandrel. As the diameter of the wound roll increases thecore slippage increases. Such individual core slippage compensates forthe normal thickness variations in the web of the particular material,thereby resulting in the winding of the individual rolls at asubstantially uniform tension.

In addition to winding each roll at a uniform tension, it is desirableto provide a roll having smooth sides, that is, wherein the side edgesof each convolution lie in a common plane. This presents a problem whenthe material is a thin film of narrow width and the winding operation isperformed at a high speed, as the entrapment of air between theoutermost convolution and the incoming strip of material causes suchstrip to wander in spite of the fact that it is under a certain amountof tension. This problem is solved by apparatus made in accordance withthis invention. Associated with each core is a guide arm 24 having oneend pivotally connected to a U -shaped support member 25 by means of adowel pin 26. The support member has a bifurcated lower end spanning arail, or trackway 27, which rail is secured in fixed position on themachine and runs parallel to the mandrel 20. A set screw 28 serves tosecure the support member to the rail after the guide arm 24 has beenproperly aligned with the associated core 20. Secured to the guide arm,at the free end thereof, is an air permeable bearing 29 and a contactroller 30, the construction of which will be described below. For thepresent, it is pointed out that a flexible tube 31, secured to the guidearm by a suitable clamp 32, has one end extending into the air bearingand the other end connected to an air manifold 33 by means of aconventional coupling 34, said manifold extending along the rail 27 andbeing secured thereto. Air, maintained under pressure within themanifold, passes through the wall of the bearing 29, whereby the strip13 is supported on a film of air as it passes to the contact roller 30.The guide arm 24 is freely rotatabie about the dowel pin 26 and thetension of the strip pressure-biases the guide roller 39 into engagementwith the wound roll 22 throughout the entire winding operation. Thedotted and solid lines show the position of the guide arm at the startand end of the winding operation, respectively. In the FIG- URE lillustration, the roll is being wound in a clockwise direction. Ifdesired, the roll may be wound in a reverse direction by passing thestrip along the right side of the contact roller instead of the leftside, as shown.

The construction and assembly of the guide arm and the associatedcomponents will now be described with reference to FIGURES 2-5. Theguide arm 24 is freely rotatable about the dowel pin 26 which isforce-fitted into align-ed holes formed in the spaced arms of thesupport member 25. A lever 35 is disposed between the spaced arms and ispivotally supported by a pin 27 force-fitted into aligned holes formedin the upper extensions of such arms. The lower portion of this lever isbiased against the arcuate end surface of the guide arm by a spring 38,said end surface having a notch 39 formed therein. Throughout the normaloperating range of rotation of the guide arm, that is, from the start tothe finish of the winding cycle, the lever is in sliding engagement withthe arcuate end of the guide arm. Upon completion of the windingoperation, the guide arm is rotated by the operator, in acounterclockwise direction until the lower end of the lever enters intothe notch 39, whereby the guide arm is then retained in the elevatedposition, thereby to facilitate the removal of the wound roll from themandrel, the insertion of new cores thereon and the attachment of theend of the strip to the new core. Thereafter, the projecting end of thelever is rotated to free the lower end from the notch and the guide armis lowered, manually, to place the contact roller into engagement withthe core.

Referring specifically to FIGURE 5, which is an enlarged cross-sectionalview taken along the line V-V of FIGURE 2, the air bearing 29 comprisesa porous tubular member made of sintered metal having a tapered holeformed in the end wall. A metal bushing has a shank 40 force-fitted intoa hole formed in the guide arm 24-, a flange portion 41 partiallydisposed within a bore formed in the guide arm, and an axial portion 42having a threaded hole formed therein. A flat head, socket cap screw 43secures the tubular member 29 to the bushing. The end of the flexibletube 31 passes through a radial hole formed in the bushing shank and issecured in place by cement. The open end of the tube 31 communicateswith a hole 44 formed in the bushing and terminating at the surface ofthe flange portion 41. Thus, an air passageway is provided between theend of the flexible tube 31 and the inner wall of the airpermeabletubular member 29. With a suitable air pressure maintained Within theflexible tube, air flows continuously through the interstices existingin the wall of the tubular member. Consequently, that portion of thestrip 13 passing over the tubular member, or air bearing 29, issupported by a film of air. The air bearing has an axial length somewhatgreater than the width of the strip 13, and easily is replaced by abearing of shorter or longer length when a strip of different width isto be wound into roll form. FIGURE 6 shows an air bearing 29 of modifiedconstruction. In this case, the bearing is made of metal having aplurality of small, radial holes drilled through the wall and a taperedhole formed in the end wall, the latter hole accommodating the head ofthe fastening screw 43, see FIGURE 5.

With continued reference to FIGURE 5, the contact roller 30 comprises aresilient band 45, made of a soft material such as, for example, gumrubber, cemented to a metal ring 47. A pair of ball bearings 43 havetheir inner races force-fitted over the rod 43 and their outer racesforce-fitted into the ring 47. The guide arm 24 is provided with a holefor receiving the rod 49, which hole is intersected by a slot (seeFIGURES 2 and 4), whereby the rod can be secured to the guide arm by thescrew 51. The roller is freely rotatable about its bearings and isaligned with the air bearing 29. When assembled on the machine, theguide arm 24 is positioned to lie in a plane such that the side edge ofthe incoming strip of material 13 is in positive engagement with theflange 41 of the metal bushing. Inasmuch as the strip, at this point, issupported on a film of air, the effective pressure of the strip againstthe flange, during the winding operation, is a minimum value, therebyeliminating curling over of the strip edge, or distortion of the stripby reason of uneven tension applied thereto. Thus, the air bearingmaintains the strip in a precise path of travel as it passes over to theproximate contact roller and onto the core. Since the contact roller ispressure-biased to ride on the outermost convolution of the roll, airentrapment is eliminated. Further, the air-floating arrangement formaintaining alignment of the strip and the use of a soft contact rollereliminates damage of the strip as by scratching of the surface. Thesefeatures make it possible to wind narrow strips of thin film havingcoated surfaces, such as adhesive, oxide, etc., into smooth rolls athigh speeds.

For certain applications, the contact roller may be provided withintegral flanges 53, as shown in FIGURE 7, the axial spacing at the baseof the flanges being a few thousandths of an inch greater than the widthof the particular strip to be wound. These flanges span the roll andserve to limit lateral excursions of the guide arm during the windingoperation. Also, in the case of certain materials, it is advantageous tohave a significant length of the strip approach the roll in a tangentialplane. Such winding arrangement is shown in the fragmentary, elevationalView of FIGURE 8. Here, the guide arm 24' carries two air bearings 29with air, under pressure, directly to each bearing by the flexible tubesand '56 which are connected to the delivery tube 31 by a suitableT-fitting 57.

Having now described the invention, those skilled in this art will beable to make various changes and modifications without thereby departingfrom the spirit and scope of the invention as recited in the followingclaims.

I claim:

1. In a machine for winding a strip of thin material on a core carriedby a mandrel, the combination of,

(a) an arm pivotally mounted for rotation in a plane parallel to that ofthe core,

(b) a bushing carried by the said arm and having a flange,

(c) a tubular member removably secured to the bushing and over which thestrip of material passes, said member having a plurality of airpassageways formed through the wall thereof, and the outside diameter ofthe said member being less than that of the said flange,

(d) means maintaining air under pressure within the tubular member, and

(e) a rotatable contact roller carried by said arm, the peripheralsurface of the roller being in engagement with the strip of material asit is wound on the core.

2. The invention as recited in claim 1, wherein the said tubular memberis made of a sintered material and having air-permeable walls.

3. The invention as recited in claim 1, wherein the said tubular memberis made of a solid material having a plurality of radial holes extendingtherethrough.

4. The invention as recited in claim 1, including a second similartubular member carried by said arm, and means maintaining air underpressure within the second tubular member, the strip of material passingover both of the tubular members.

5. The invention as recited in claim 1, including a rail secured to themachine and disposed in spaced, parallel relation to the mandrel, asupport member slidably carried by the rail, and means for securing thesupport member to the rail, the said arm being pivotally connected tothe support member.

6. The invention as recited in claim 5, including cooperating means onthe said arm and support member for retaining said arm in a positionwherein the free end thereof is spaced a predetermined distance from thecore.

7. The invention as recited in claim 1, wherein the said contact rollerhas an outer surface made of a soft resilient material.

8. A machine for winding strips of material into individual rolls andcomprising,

(a) a mandrel carrying a plurality of cores onto which the strips ofmaterial are to be wound,

(b) a rail secured in spaced, parallel relation to said mandrel,

(c) a plurality of guide arms and support members, each arm having oneend pivotally connected to an associated support member,

(d) means securing each support member to said rail,

(e) a tubular member carried by each arm at the free end thereof, eachsuch member having a plurality of air passageways formed through theWall thereof,

(g) a rotatable contact roller carried by each guide arm proximate tothe associated tubular member, the recited arrangement being such thatthe strips of material pass over the associated tubular members on theirway to the core and the peripheral surfaces of the contact rollers arein engagement with the strip of material as it is wound on the core.

9. The invention as recited in claim 8, wherein the contact rollers aremade of a soft resilient material and the tubular members are made of asintered material and have air permeable walls.

10. The invention as recited in claim 8, wherein each tubular member hasan end abutting a flange formed on a bushing which is secured to theassociated guide arm, and wherein such flange has a diameter exceedingthat of the tubular member.

11. The invention as recited in claim 8, including manually-operablemeans for retaining each guide arm in a position wherein the free endthereof is spaced a predetermined distance from the associated core.

References Cited UNITED STATES PATENTS 2,611,552 9/1952 Nystrand 242-66X 3,055,605 9/1962 Young et al 242--56.4 3,087,664 4/1963 Streeter 24276X 3,143,267 8/1964 Maxey 226- 3,224,698 12/1965 Conti 242-66 3,281,04010/1966 Grant 242-76 X 3,298,624 1/ 1967 Schott 242-67.1 X

WILLIAM S. BURDEN, Primary Examiner.

